Privacy Policy
Effective 2026-10-02
The Korean version of this policy governs. If a translation differs, the Korean version prevails.
INHO LEE (“we”) operates bichoning (the “Service”). We handle the personal information of people who use the Service with care and comply with Korea’s Personal Information Protection Act and other applicable laws. This policy explains what we collect, why, and how we handle it.
1. Information we collect
You can use the Service without an account. We collect the following only if you sign up or turn on app notifications. If you watch an ad in the app, Google collects some information directly (see the last item below). If you send feedback, we also receive what you write.
- At sign-up: email address, password, and a security question with its answer for password recovery
- While you use the Service (members): sentences you practiced with the date and time zone, your interface language, and the last lesson you viewed
- Automatically: access time, IP address, and browser/device information (server logs)
- If you turn on app notifications (even without an account): your device’s notification token, your chosen language, and your device’s time zone
- If you watch an ad in the app (app only): Google (AdMob) directly collects device and app information, IP address, and ad views and clicks to show and measure ads, and collects your advertising identifier (IDFA) only if you allow tracking. We do not receive this information.
- If you send feedback (even without an account): what you write, your language, whether you used the app or the website, and the screen you sent it from. If you are signed in, it is linked to your account.
We do not collect your name, phone number, contacts, or payment information. We do not track your activity across other apps or websites. Ads in the app use your advertising identifier for personalized ads only if you allow tracking on your device; you can use every feature the same way if you don’t.
2. How we use it
- To identify you, sign you in, and reset your password
- To show your practice history and streak
- To remember your language and last lesson so you can pick up where you left off
- To keep the Service stable and fix errors
- To send you the Expression of the Day at your device’s local time, in your chosen language
- To show rewarded ads that unlock sentences in the app (unlock records are stored only on your device)
- To read your feedback and improve the Service
- To let you know when a new lesson is out (you can turn this off in Settings separately from the Expression of the Day)
3. Retention and deletion
Your account and practice history are deleted immediately when you delete your account (Settings → Account → Delete account). Deleted data cannot be recovered.
Server logs and backup copies are deleted according to our service providers’ retention schedules. Where the law requires us to keep certain records, we store them separately for the required period.
Notification data is deleted immediately when you turn notifications off in Settings. If you delete the app, it is deleted as soon as the delivery service tells us.
Feedback from members is deleted when the account is deleted. Feedback sent without an account is kept as long as needed to read it and improve the Service, then deleted. If you included contact details or other personal information, it is kept with the feedback; contact us below to have it deleted.
4. Sharing with third parties
We do not share your personal information with third parties, except where required by law.
5. Service providers and international transfer
We use the providers below to run the Service. Their servers are located outside Korea, so your information is transferred internationally over the network when you use the Service. The data involved is listed in section 1 and kept as described in section 3.
| Provider | Country | Purpose |
|---|---|---|
| Supabase Inc. | United States (AWS us-west-2, Oregon) | Authentication and database hosting |
| Vercel Inc. | United States | Web hosting |
| 650 Industries, Inc. (Expo) | United States | Sending app notifications (relayed to Apple and Google notification services) |
| Google LLC (AdMob) | United States | Showing and measuring in-app ads (rewarded ads, app only) |
Ads in the app are handled by Google LLC under Google’s Privacy Policy (https://policies.google.com/privacy). We ask for consent to personalized ads the first time you watch an ad, and you can change it anytime under Tracking in your device settings.
6. Your rights
You may access, correct, or delete your personal information, or ask us to stop processing it, at any time. You can delete your account directly in the app; for other requests, contact us below and we will respond without delay.
7. Security
- All traffic is encrypted with HTTPS.
- Passwords and security answers are stored as one-way hashes; even we cannot read them.
- Database access is restricted row by row so that each person can reach only their own records.
8. Cookies
The Service stores the following cookies on your device. None are used for advertising or tracking.
mochi_locale— Interface languagemochi_lesson— Last lesson viewedmochi_onboarded— Whether the intro was shownmochi_tour— Whether the tutorial was shownmochi_push— Whether app notifications are on (in the app only)mochi_push_lessons— Whether you get new lesson alerts (in the app only)sb-*— Keeping you signed in (members only)
You can block cookies in your browser settings. If you do, your language will not be remembered and you will not stay signed in.
9. Children
The Service does not accept sign-ups from children under 14.
10. Contact
- Privacy officer: INHO LEE
- Email: sayyou0918@gmail.com
11. Changes
We will announce changes to this policy in the Service at least 7 days before they take effect.